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c++ - How to generate random number within range (-x,x)

Hi It is possible to generate random number within a range (-x,x) using rand()?? If not, how can I generate random number withing that range ?

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// return a random number between 0 and limit inclusive.
int rand_lim(int limit) {

    int divisor = RAND_MAX/(limit+1);
    int retval;

    do { 
        retval = rand() / divisor;
    } while (retval > limit);

    return retval;
}

// Return a random number between lower and upper inclusive.
int rand_lim(int lower, int upper) {
    int range = abs(upper-lower);

    return rand_lim(range) + lower;
}

As usual, all the others I've seen in this thread can/will produce at least slightly skewed results.


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